feat: transport incidents with truck number support

- DB: trucks table + incidents.truck_id FK + transport enum value
- Validation: transport type requires truck_id
- Create API: validates truck exists/active, persists truck_id
- Report form: truck dropdown shown when type=transport (required)
- Admin: TruckManager CRUD + /api/admin/trucks route
- Detail: trucks join surfaced in incident-detail + detail page query
- Inbox (HSE + supervisor): truck filter, transport in TYPE_OPTIONS,
  fixed stale enum values (dropped dangerous_occurrence/mhe_asset/occupational_disease)
- List: transport label + truck number badge in rows
- i18n: transport + truckLabel/truckPlaceholder in en/ms/zh

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CPf5Rc8QPx6V8KLEEgfKEQ

app/api/admin/trucks/route.ts

@@ -0,0 +1,34 @@
+export const dynamic = 'force-dynamic'
+
+import { NextRequest, NextResponse } from 'next/server'
+import { requireAdmin } from '@/lib/auth/require-admin'
+
+export async function POST(request: NextRequest) {
+  const { supabase, user } = await requireAdmin()
+  if (!user) return NextResponse.json({ error: 'Forbidden' }, { status: 403 })
+
+  const body: { truck_no?: string; carrier?: string } = await request.json().catch(() => ({}))
+  const truck_no = (body.truck_no ?? '').trim()
+  if (!truck_no) return NextResponse.json({ error: 'truck_no required' }, { status: 422 })
+
+  const { data: truck, error } = await supabase
+    .from('trucks')
+    .insert({ truck_no, carrier: (body.carrier ?? '').trim() || null })
+    .select('id')
+    .single()
+
+  if (error || !truck)
+    return NextResponse.json(
+      { error: error?.code === '23505' ? 'Truck number already exists' : 'Insert failed' },
+      { status: 400 },
+    )
+
+  await supabase.rpc('write_audit_log', {
+    p_table_name: 'trucks',
+    p_record_id: truck.id,
+    p_action: 'INSERT',
+    p_new_value: { truck_no, carrier: (body.carrier ?? '').trim() || null },
+  })
+
+  return NextResponse.json({ id: truck.id }, { status: 201 })
+}